Phonograph-controlling mechanism



1.564.833 w. w. DEAN PHONOGRAPH CONTROLLING MECHANISM Original FiledJune 20. 1919 Dec. 8, 1925- W. W. DEAN INVENTOR.

BY WY /Qh #L, ATTORNEYS Patented Dec. 8, 1925.

UNITED STATES PAT'ENT OFFICE.

WILLIAM W. DEAN, OF LOWELL/MASSACHUSETTS, ASSIGNOR TO THE EFFICIENCYELECTRIC CORPORATION, OF NEW] YORK, N. Y., A CORPORATION OF NEW YORK.

PHONOGRAPH CONTROLLING MECHANISM.

Original application filed June 20, 1919, Serial No. 305,527. Dividedand this application filed February To all whom it may concern:

Be it knownthat I, WILLIAM W. DEAN, a citizen of the United States,residing at Lowell, in the county of Middlesex and State ofhlassachusetts, have inventedrcertain new and useful Improvements inPhonograph-Controlling Mechanisms; and I do hereby declare the followingto be a full,

clear, concise,and exact description of the invention, such as willenable those skilled in the art to which my invention appertains to makeand use the same.

My invention relates to motor governing devices, and more particularlyto such governing devices as may be used in connect-ion with motorsrequired to be operated at a constant speed, as, for instance,phonograph motors and the like, although I may employ the device of myinvention wherever such a device finds a use. 7

It hasbeen previously proposed to control the speed of a motor, such aselectric motors, for driving the turn-table of a phonograph, bycentrifugally operated electric contacts, the same controllingelectric'circuits adapted under the control of these centrifugallyoperated contacts to retard the speed of the motor, so that the motorcannot exceed a given predetermined speed which is substantially thatspeed required to actuate the centrifugally operated contacts.

The object of the present invention is to provide an improved motorgovernor, of the weighted type, which .is efficient and uniform inoperation, which is capable of being maintained in a given condition ofadjustment and which is inexpensive to manufacture and which may bemanufactured in large quantities with the uniformity of resultantproduct.

The object of thepresent invention is to provide a reed spring governorwherein the electrical contact carried by the reed is shifted in a linecoincident with the axis of rotation of the motor shaft, and which reedspring may be secured directly to the motor shaft without the necessityof providing a separate mount for the same.

Other objects of my invention, and the invention itself will be madeplainer to those skilled in the art to which my invention appertains byreference to the drawing accompanying this specification and whichSerial No. 539,323.

drawing shows a preferred embodiment of my invention.

Referring to the drawings- Fig. 1 shows an embodiment of my inventionpartly in elevation and partly in section.

Fig. 2 shows a different form in which my invention may be embodied.

Referring now to Fig. 1, at TN, I show a phonograph turn-table which isrequired to be driven by an electric motor M at a constant speed. Theworm gear VG is interposed between the turn-table and the motor shaft SSso that the said shaft communicates motion to the said turn-table. Athrust spring S and thrust bearing TB is provided for the motor shaft toprevent longitudinal displacement of the said shaft when the motor isoperated. This spring may be formed by bending a flat leaf spring intothe form of a loop and'securing both ends by the machine screw 2, or bymaking the sprin in a single endless loop, as illu trated. The spring,however, will be made sulliciently thin for the purposes hereinafter setforth, and have sufficient width as to prevent distortion when the motoris operated to rotate the spring loop rapidly such as at a speed ofsubstantially 1100 R. P. M., which speed I find to be a convenient oneto use for the purpose of driving the turntable TN.

. At the other end of the loop and disposed in line with the axis ofrotation of the shaft SS, is an electrical contact SC carried by thespring. lVeights V and W are riveted to the spring LS on that side ofthe loop towards the supporting shaft SS, and at points on either sideof the shaft SS, and between the shaft and the outer portions of theloop most distant from the axis of rotation thereof. When the motor isoperated to drive the shaft SS to a predetermined speed which may be aspeed of substantially 1100 R. P. M., the weights and Vi under theaction of centrifugal force, will deform the shape of the loop in such away that the side of the loop to which the electrical contact SC issecured, will be moved axially of the shaft SS and in a direction awa Yfrom the end of the said shaft, thus at a critical speed determined bythe mechanical dimensions of the spring LS andthe weight thereof, andthe weight of the weights and W the con tact SC carried by the springwill engage the stationary electric contact CE.

When this occurs, an electrical circuit will be completed bridging theelectrical circuit conductors 3 and 4 which lead from a source ofenergizing current which may be an alternating or a direct currentsource, and which bridged circuit comprises the winding flV of the.relay U, the contact seat comprising the contacts SC and CE, and thecircuit eonductors 7 and 8 leading from the mains 3 and 4 to thecontactCE and the relay U respectively.

As long as this circuit is closed by the en gagement of the contacts CEand SC, the relay U will attract its armature, breaking the contacts 9which normally are bridged across the terminals of a resistance coil 10,thereby introducing into the energizing circuit of the motor M, theresistance coil 10, to cut down the supply of current to the said motor.The relay U will preferably be of the quick acting type, and the motorenergizing current being diminished by the breaking of the contacts 9,the speed at which the shaft SS is rotated will immedi ately be reduced,and the centrifugal force diminishing will cause a re-opcning ofthecontacts CE and SC substantially as set forth in my co-pendingapplication Serial No. 297,621, fled May 16, 1919.

This application is a division of my application Serial No. 305,527,filed June 20, 1919;

As described above, the electrical contacts in the circuit of the relayU will be closed,

and consequently immediately re-opened and at all. times during theoperation of the motor M there will be a continuous closing and: openingof these contacts, the relative length of time that the contacts areclosed to. the length of the periods during which they are openeddetermining the speed ofdetermined, which i s.not possible with othertypes of governing springsv having. more than one point of support.

Referring now tov the embodiment of my invention illustrated in. Fig, 2-7 Instead oftheclosed loop spring of Fig. 1, I herein. employ a loopspring which is substantially U-shaped, the spring carried contact SCbeing also axially disposed, but in this case I place the weight on thatarm of the U-shaped spring farthest away from the supporting shaft SS,so. thatthe weight IV, when operated upon by centrifugal force caused bythe rotation of the shaft, will most efficiently move the contact in anaxial direction.

Having thus describedmy invention. in a plurality of embodiments, I amaware that numerous and extensive departures may be made from theembodiments hereinillustrated and described, but without departing fromthe spirit ofmy invention.

I claim 1. In an electric governing switch for controlling the speed ofan electric motor, a

pair of speed controlling switch contacts, a motor shaft carried loopreed springcarrying one of the said contacts substantially in line withthe axisof rotation of'the motor shaft, said spring being secured atasingle point in said axial line-and weight members secured to said loopspring in alignment with said shaft center, said one contactbeingmovable outwardly from beyond the shaft end upon an increase of shaftrotational speed, the other contact being stationary andadaptedtobeengaged by said one contact.

2. In a switch for controlling the speed of an electric motor aloopedreed'spring carried on the end of armotor by beingsecured at a singlepoint thereto and being. rotatable thereby, a pair of switchcontacts,one of said contacts being stationary and the other being: carried onthe said spring inline with theaxis of rotation of the motor shaftandweights carried by said loop, said contact being movable axially uponchanges in rotational speed, said spring carried contact movingoutwardly axially from the shaft end upon an increase of speed tocontactwith the said stationary contact.

3. In a switch for controlling the speed of an electric motor, astationary contact, a

motor shaft, a closed loop spring carried onthe end of the motorshaftbeing secured at asingle point thereto and being rotatable thereby, acontact carried by said closed loop spring in line with the axis ofrotation of the motor shaft, and weights carried by the spring,saidmovable contact bein movable axially of themotorshaft upon c liangesof rotational speed.

at. In a switch for controlling the speedof an electric motor, astationary contact, amotor shaft, a closed loop spring-carriewon the endof the motor shaft being secured at asingle pointthereto and beingrotatable thereby, a contact'carried by said closed loop spring atapoint'opposite the point of' support and axially of the'supportingmotor shaft, and weights carried by the spring,

said movable contact being movable axially of the motor shaft uponchanges of rotational speed.

5. In a switch for controlling the speed of an electric motor, astationary contact, a motor shaft, a closed loop spring carried on theend of the motor shaft being secured at a single point thereto and beingrotatable thereby, a contact carried by said closed loop spring at apoint opposite the point of sup port and axially of the supporting motorshaft, and Weights carried by the spring, said movable contact beingmovable axially outwardly of the motor shaft upon changes of rotationalspeed.

In Witness whereof I have hereunto set my hand this 20th day ofFebruary, 1922. WM. XV. DEAN.

